This invention relates to the treatment of oleaginous seed material, and more particularly to the treatment of defatted oleaginuous seed material to form a proteinaceous product.
Oleaginuous seed materials, such as soybeans, cotton seeds, peanuts, sesame seeds, sunflower seeds, rapeseed, and the like contain proteinaceous matter of a highly nutritious nature have found many uses in the arts. Soybeans for example, after oil extraction, have been treated to recover the proteinaceous matter for use in diverse industrial processes, e.g. in the paper, plastic and food industries.
Many processes are being practiced with the most common process including the step of contacting the oleaginous seed material in flake or meal form with an organic solvent to extract oil therefrom thereby forming a defatted residual seed material which is contacted with an alkali solution to dissolve the proteinaceous matter subsequently precipitated by an acid, such as described in U.S. Pat. No. 2,589,867 to Circle. The proteinaceous matter recovered is generally referred to as an "alkali-soluble, acid precipitated protein".
In another process, defatted soybean flakes are contacted with an acidic solution to dissolve primarily the non-proteinaceous matter including certain enzyme systems, ash flavoring, ingredients and carbohydrates, such as saponin, sucrose, raffinose and stachyose together with minor quantities of proteinaceous matter, with the residual substance being utilized as a proteinaceous composition in the food industry, such as described in U.S. Pat. No. 2,881,076 to Sair.
In still another process, the defatted soybean flakes are treated with an aqueous alcohol solution to extract the non-proteinaceous matter, primarily the carbohydrates (sometimes referred to as "whey"), with minimal extraction of water soluble proteins, such as described in U.S. Pat. No. 3,307,744 to O'Hara et al or U.S. Pat. No. 3,365,440 to Circle et al. As used herein the term "miscella" refers to a solution of extracted soluble matter in an extraction solvent.
While the latter two processes have been effective in producing protein concentrates, the quantity of the whey remaining in the product concentrate has limited its application for certain end uses. Additionally, such processes suffered from large liquid to solids ratio which place excessive loads on the desolventizer apparatus. The steam requirement to recover solvent has been excessive as well as requirements for additional heat transfer capabilities in the processes.